1. Field of the Invention
The present invention relates to a lens barrel, and in particular, relates to a backlash eliminating structure of a lens barrel including two optical elements one of which is positioned in front of the other.
2. Description of the Related Art
In photographing lenses (photographing lens barrels) such as zoom lenses which include one or more optical elements that move in an optical axis direction when a focal-length varying operation (zooming operation) is performed, a backlash eliminating structure for movable members which move in the optical axis direction is essential. This type of backlash eliminating structure (e.g., disclosed in Japanese Unexamined Patent Publication No. 2004-170961, Japanese Unexamined Patent Publication No. 2006-337563) requires many springs and thus tends to be complicated in structure.